Hi,
I just wanted to know if anybody has logged any figures for the advance they get on the 380, and if it's as poor as mine. I see an absolute best of +29 at no load on a cold engine at really low RPM, only lasts until the coolant temp hits about 85 degrees. Once warm (Coolant about 90+) the best I see is around 9-10 at high load and RPM (5000+), and about 13-15 max at medium load. I'm generalising a bit here, but this is very typical for my car, and hasn't changed much even with intake, exhaust mods and MAF interceptor (to adjust AFR's).
I'm trying to work out of this is due to knock retardation (hard to tell from OBD logs), or just VERY conservative tuning from the factory.
If it's the former, does anyone know what makes the 380 so prone to detonation under high torque? I've seen very likely evidence of pinging on gear change at WOT, as the retard is very severe, beyond the typical torque control figures you would expect to see (-21 is the worst I've seen at 4500 RPM).

Also does anyone have a suggestion for the best way of spotting knock from OBD diagnostics? I've just been looking for sudden and atypical retardation, but I don't see much that is not associated with a gear change or decelleration., AFR's are narrowband so too hard to tell from those. I've been advised to retard my timing to cope with the mods I've done, which makes sense (leaner fuel and MUCH more airflow), but the timing seems very retarded already, so I'm trying to work out if this is atypical and due to knock (if this is the case, then I'm pretty worried cos' it must be pinging it's nuts off consistently) or just the factory tune
I know this is kinda model specific, but hopng to get more technical input

ODB2 appears to support "knock count", which would normally be a count of detected knock events in some period, but it may be manufacturer specific.

Your best bet for determining whether the knock is real is probably to monitor the output of the knock sensor itself - you'd need some sort of amplifier that could treat the sensor as a high impedance microphone, and listen through headphones (while someone else drives) or record for later listening.

There's an article on Autospeed about modifiying a "personal amplifier" for knock monitoring; don't have a link but searching for Whisper 2000 should find it. The Whisper amplifier is no longer available, but I found an article from someone who modified a similar device (ListenUp?) in the same way.

First time I drove a 380 I was surprised how well it went at low revs, but I was disappointed at how much retard it threw in when you really put your foot down. It stands to reason though, with such huge pistons ignition timing needs to be wound back under duress to protect the piston tops, big end bearings etc. Your numbers are probably typical of the 380 engine. It also explains why fuel consumption gets poor when you burry the right foot too often. At least you now know how to drive for best ignition advance and hence best fuel economy. lol

Hi,
I just wanted to know if anybody has logged any figures for the advance they get on the 380, and if it's as poor as mine. I see an absolute best of +29 at no load on a cold engine at really low RPM, only lasts until the coolant temp hits about 85 degrees. Once warm (Coolant about 90+) the best I see is around 9-10 at high load and RPM (5000+), and about 13-15 max at medium load. I'm generalising a bit here, but this is very typical for my car, and hasn't changed much even with intake, exhaust mods and MAF interceptor (to adjust AFR's).
I'm trying to work out of this is due to knock retardation (hard to tell from OBD logs), or just VERY conservative tuning from the factory.
If it's the former, does anyone know what makes the 380 so prone to detonation under high torque? I've seen very likely evidence of pinging on gear change at WOT, as the retard is very severe, beyond the typical torque control figures you would expect to see (-21 is the worst I've seen at 4500 RPM).



HI

Had a look at a couple of log files I got via dashcommand/ScanXl - in *.lgf format - happy to send them too u if you can read and do the detailed analysis

I know one was petrol and think the other one LPG, but not 100%

Petrol gvae max 30.5, min -9 average +8.9

Other one Max 24.5 min -16 avg 7.5

Happy to record some more - let me know what sort of driving range interests you - typical city, WOT runs etc


Have emailed 2 files and screens shots to you also

HI

Had a look at a couple of log files I got via dashcommand/ScanXl - in *.lgf format - happy to send them too u if you can read and do the detailed analysis

I know one was petrol and think the other one LPG, but not 100%

Petrol gvae max 30.5, min -9 average +8.9

Other one Max 24.5 min -16 avg 7.5

Happy to record some more - let me know what sort of driving range interests you - typical city, WOT runs etc


Have emailed 2 files and screens shots to you also


HI

Had a look at a couple of log files I got via dashcommand/ScanXl - in *.lgf format - happy to send them too u if you can read and do the detailed analysis

I know one was petrol and think the other one LPG, but not 100%

Petrol gvae max 30.5, min -9 average +8.9

Other one Max 24.5 min -16 avg 7.5

Happy to record some more - let me know what sort of driving range interests you - typical city, WOT runs etc


Have emailed 2 files and screens shots to you also

Thanks Terry,
will def take a look at your logs. I mostly pay attention to the advance I get at RPM under full load, i'll post some log entries up later to show what I'm talking about
EDIT: Terry unfortunately I changed ISP's and my email address was out of date, so I won't get those logs. Fixed it now, would you mind re-sending?
Cheers
RG

WytWun: Unfortunately I don't get this PID (knock) I don't think the 6G75 supports it?

You could always advance the ignition timing throughout the range if you have the expertise to remap the ECU, then put an amplifier circuit onto the knock sensor to work a light on the dash. That way you can back off when the light starts flashing. lol Your motor might not like it though. The factory map would be a good compromise between preserving the engine and fuel economy, with a safety margin thrown in. Experiment away though, its your engine. Personally I like photos of melted pistons. lol

http://www.max-boost.co.uk/max-boost/images/LET/melted_piston.jpg


http://www.max-boost.co.uk/max-boost/Gifs/grim_reaper_slashing_md_wht.gif

Unfortunately no-one has the expertise to do anything to the 380 Bosch ECU, still in un-cracked status, lots of talk about soon .. maybe, but stil nothing so far. That's why everyone is using Exede interceptor's etc.
I would like to build a circuit to use the Factory Knock sensor, trouble is that the ECU filters this for knocks near TDC to avoid all the noise, so I'll get a lot of "knocking" from the sensor , that isn't actualy detonation
Love the piston, what was that: NOS at 1000 RPM, and 50 degrees of advance?

The knock sensor is like a microphone, so - in theory - any microphone amp circuit connected across it should pick up the noise.

Piston - mmmm - not mine fortunately, but from the way the rings melted and the sides of the pistons went, I'd guess NOS and too much advance as you suggest. lol

Thanks Terry,
will def take a look at your logs. I mostly pay attention to the advance I get at RPM under full load, i'll post some log entries up later to show what I'm talking about
EDIT: Terry unfortunately I changed ISP's and my email address was out of date, so I won't get those logs. Fixed it now, would you mind re-sending?
Cheers
RG

WytWun: Unfortunately I don't get this PID (knock) I don't think the 6G75 supports it?

Resent to new email addy

I dont get a knock sensor record - just timing settings, mapped against rpm, load %, inlet air temp, MAF, MAP etc

I would like to build a circuit to use the Factory Knock sensor, trouble is that the ECU filters this for knocks near TDC to avoid all the noise, so I'll get a lot of "knocking" from the sensor , that isn't actualy detonation.

You may find this interesting: Knock Sensor Sounds (http://home.netcom.com/~bsundahl/knock/sound/KnockSounds.htm)

Once you know what to listen for, you'll be able to hear it through all the rest of the signal.

First time I drove a 380 I was surprised how well it went at low revs, but I was disappointed at how much retard it threw in when you really put your foot down. It stands to reason though, with such huge pistons ignition timing needs to be wound back under duress to protect the piston tops, big end bearings etc. Your numbers are probably typical of the 380 engine. It also explains why fuel consumption gets poor when you burry the right foot too often. At least you now know how to drive for best ignition advance and hence best fuel economy. lol

To be correct, OP's numbers are likely to be representative of the 6G75 when tuned within the constraints of the exhaust system and emissions targets of the 380.

Fit a 6G75 to a Magna (with Magna exhaust and ECU), and the ignition map can be very much like the stock 6G74 ignition map.

The pre-cats are a major source of limitation in the 380, and the AFRs and timing under heavy load are part of the plan to keep them within certain temperature limits to ensure ADR compliant operation over their design life.

The pre-cats are a major source of limitation in the 380, and the AFRs and timing under heavy load are part of the plan to keep them within certain temperature limits to ensure ADR compliant operation over their design life.

This is true and also why the cams are retarded.